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  • 1
    Electronic Resource
    Electronic Resource
    Two types of amino acid substitutions in protein evolution (1979)
    Springer
    Journal of molecular evolution 12 (1979), S. 219-236 
    Details
    ISSN: 1432-1432
    Keywords: Amino acid substitution ; Physico-chemical difference ; Conservative ; Low-constraint ; Protein evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The frequency of amino acid substitutions, relative to the frequency expected by chance, decreases linearly with the increase in physico-chemical differences between amino acid pairs involved in a substitution. This correlation does not apply to abnormal human hemoglobins. Since abnormal hemoglobins mostly reflect the process of mutation rather than selection, the correlation manifest during protein evolution between substitution frequency and physico-chemical difference in amino acids can be attributed to natural selection. Outside of ‘abnormal’ proteins, the correlation also does not apply to certain regions of proteins characterized by rapid rates of substitution. In these cases again, except for the largest physico-chemical differences between amino acid pairs, the substitution frequencies seem to be independent of the physico-chemical parameters. The limination of the substituents involving the largest physicochemical differences can once more be attributed to natural selection. For smaller physico-chemical differences, natural selection, if it is operating in the polypeptide regions, must be based on parameters other than those examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01732340
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  • 2
    Electronic Resource
    Electronic Resource
    Molecular evolution of mRNA: A method for estimating evolutionary rates of synonymous and amino acid substitutions from homologous nucleotide sequences and its application (1980)
    Springer
    Journal of molecular evolution 16 (1980), S. 23-36 
    Details
    ISSN: 1432-1432
    Keywords: Amino acid difference ; Synonymous difference ; Selective constraint ; mRNA evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A method for estimating the evolutionary rates of synonymous and amino acid substitutions from homologous nucleotide sequences is presented. This method is applied to genes of øX174 and G4 genomes, histone genes andβ-globin genes, for which homologous nucleotide sequences are available for comparison to be made. It is shown that the rates of synonymous substitutions are quite uniform among the non-overlapping genes of øX174 and G4 and among histone genes H4, H2B, H3 and H2A. A comparison between øX174 and G4 reveals that, in the overlapping segments of the A-gene, the rate of synonymous substitution is reduced more significantly than the rate of amino acid substitution relative to the corresponding rate in the nonoverlapping segment. It is also suggested that, in the coding regions surrounding the splicing points of intervening sequences ofβ-globin genes, there exist rigid secondary structures. It is in only these regions that theβ-globin genes show the slowing down of evolutionary rates of both synonymous and amino acid substitutions in the primate line.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01732067
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Evolutionary changes of nucleotide sequences of papova viruses BKV and SV40: They are possibly hybrids (1982)
    Springer
    Journal of molecular evolution 19 (1982), S. 72-79 
    Details
    ISSN: 1432-1432
    Keywords: Sequence Difference ; Recombination ; Overlapping genes ; Functional constraint
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Complete nucleotide sequences were compared between papova viruses BKV and SV40 and the degrees of sequence divergences were compared between structurally and/or functionally different segments or genes in details. It was shown that the rate of synonymous substitution is not only very high but also approximately uniform among different genes in these viruses as in eukaryotic genes examined to date. While all the non-coding regions including the intron showed marked sequence preservation which is in sharp contrasted with the case of eukaryotic genes where the large bulk of non-coding regions evolve at a rate as rapidly as that of synonymous substitution. It is remarkable that a long continuous stretch of sequence including the putative VPX gene and a 5′ half of VP2 gene showed strong homology between BKV and SV40. A close examination of the pattern of base substitutions revealed that this unusual homology was derived by recombination between the two viruses during their evolution. On the basis of the pattern of base substitutions and the bias in code word utilization, we also showed that the putative VPX gene actually could code for a functional polypeptide. In papova viruses, the 3′ terminal sequence of VP2/3 gene overlaps with the 5′ terminal sequence of VPI gene. The pattern of base substitutions in the overlapping segment was examined in detail in comparison with those in the non-overlapping portions of VP2/3 and VP1 genes. It was shown that the evolutionary mode of the overlapping genes is in good agreement with our previous prediction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02100225
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  • 4
    Electronic Resource
    Electronic Resource
    Sequence similarity between EGF receptor and α 1 -acid glycoprotein (1985)
    [s.l.] : Nature Publishing Group
    Nature 314 (1985), S. 199-199 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE human epidermal growth factor (EGF) receptor precursor consists of three domains, an extracellular EGF binding domain, a single transmembrane domain and a cytoplasmic domain. Ullrich et a/.1 recently determined the complete amino acid sequence of the molecule and showed that the latter two ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/314199a0
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  • 5
    Electronic Resource
    Electronic Resource
    Inhibition of retroviral protease activity by an aspartyl proteinase inhibitor (1987)
    [s.l.] : Nature Publishing Group
    Nature 329 (1987), S. 654-656 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Alignment of the amino acid sequence of retrovirus enzyme protease and the sequence deduced from the cloned viral DNA shows that the protease is encoded by a 5; region of the pol gene6'8, though avian viral protease is an exception encoded by a 3' portion of the gag gene5. It was proposed that ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/329654a0
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  • 6
    Electronic Resource
    Electronic Resource
    A novel common missense mutation G301C in the N-acetylgalactosamine-6-sulfate sulfatase gene in mucopolysaccharidosis IVA (1997)
    Springer
    Human genetics 〈Berlin〉 101 (1997), S. 97-101 
    Details
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disorder caused by a genetic defect in N-acetylgalactosamine-6-sulfate sulfatase (GALNS). In previous studies, we have found two common mutations in Caucasians and Japanese, respectively. To characterize the mutational spectrum in various ethnic groups, mutations in the GALNS gene in Colombian MPS IVA patients were investigated, and genetic backgrounds were extensively analyzed to identify racial origin, based on mitochondrial DNA (mtDNA) lineages. Three novel missense mutations never identified previously in other populations and found in 16 out of 19 Colombian MPS IVA unrelated alleles account for 84.2% of the alleles in this study. The G301C and S162F mutations account for 68.4% and 10.5% of mutations, respectively, whereas the remaining F69V is limited to a single allele. The skewed prevalence of G301C in only Colombian patients and haplotype analysis by restriction fragment length polymorphisms in the GALNS gene suggest that G301C originated from a common ancestor. Investigation of the genetic background by means of mtDNA lineages indicate that all our patients are probably of native American descent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004390050594
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  • 7
    Electronic Resource
    Electronic Resource
    Effect of modification of enkephalin C-terminal functions on affinity selection of opioid receptors (1990)
    Chicester [u.a.] : Wiley-Blackwell
    Journal of Molecular Recognition 3 (1990), S. 197-203 
    Details
    ISSN: 0952-3499
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Enkephalin analogs with various C-terminal modifications have been synthesized to evaluate the corresponding structural elements in the opioid receptors. The carboxyl group of the C-terminal leucine5 or glycine5 was converted into the mercaptomethyl (-CH2SH) and hydroxymethyl (-CH2OH) groups, starting from leucinthiol or leucinol for Leu5-derivatives and from cysteamine or ethanolamine for Gly5-derivatives. Interactions of synthetic peptides with the opioid receptors were examined by the radioligand receptor binding assays using rat brain and tritiated enkephalin analogs. The data suggest that the C-terminal carboxyl group in enkephalins is important, but not electrostatically, for interaction with delta-opioid receptors. With leucinthiol-enkephalin in biological assays which examine its inhibitory activity for electrically stimulated contractions of isolated smooth muscle, it was found that the reactive thiol group exists in the mu receptors present in the guinea pig ileum. Leucinthiol-enkephalin became bound covalently to this receptor-thiol group via disulfide formation after prolonged incubation.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmr.300030505
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